15.5. Capital cost of a rural highway project is $5,000,000. This project will shorten the road by 1.2 km and reduce journey times by an average of 2 min each. The project is also ex- pected to reduce traffic accidents by an average of 6/year and to reduce annual mainte- nance costs by $2,000. Average daily traffic on this road is currently 10,000, with a load factor of 1.5 persons per vehicle. Traffic is expected to increase linearly by 8 percent over the 15 year life of the project. If vehicle operating costs are $0.12/km, travelers value their time at $3.20/h, and the average cost of a traffic accident is $25,000, what is the benefit- cost ratio? Assume an interest rate of 10 percent